Your gut microbiome

Regular readers of Wellbeing Magazine will know I have a little obsession with the human microbiome which has been ongoing now for many a year. What’s exciting is that this area of medicine, is gaining pace so quickly that everyone is being left slightly out of breath.

How does your garden grow? Well not I hope with silver bells and cockle shells – I’m talking of course about your inner garden; your unique ecosystem and how it impacts your health and well being. If you haven’t been living under a rock for the last fifteen years you will have heard of good bacteria. Found in yogurts and “probiotic” drinks on the supermarket shelves. We were told these were good for us after a course of antibiotics. These came hand in hand with “prebiotics”, foods which help the good bacteria grow. We then discovered we’d been swallowing antibiotics like smarties for far too long, taking them when we don’t need them and building up resistance.

Very quickly we then learned that we should only take antibiotics when we had a bacterial infection. GP’s stopped over prescribing them and we tried our best to stop asking for them at every cough or sniff. With the rise of hospital superbugs we then heard rumours of faecal implants, surely something from star trek and a bit of a joke, now they are being administered for c.difficule patients on the NHS.

Daily reports of how important our gut flora is for nearly every single disease state, shows us how far we have come in a very short space of time. New research articles on the gut microbiome are now linked to all manor or disease states like Alzheimers, mental health, diabetes, IBS, fertility, autoimmunity and most surprisingly weight loss. Diversity of what we eat is key – 15,0000 years ago our ancestors regularly ingested around 150 ingredients in a week, now it averages about twenty. Welcome to the fast pace of human gut flora research.

More microbe than human

In many ways you are more microbe than human. There are ten times more cells from microorganisms than from human cells in and on our bodies. Even our genes are outnumbered by one hundred to one by our microbial genes. Most of our microbes, come from our mothers breast milk and the birth canal, and the mix becomes very personal, almost like a fingerprint. Our microbes are super busy; educating our immune cells, providing the first line of defence, protecting our health, they even spew out their own antibiotics – how cool is that! The types vary depending on where they live: mouth, nose, armpit, forearm, scalp, where they have all happily adapted to their habitats. However the largest number is in our gut where we have the most complex and diverse ecosystem fighting infection, regulating metabolism and regulating how much energy we burn and fat we store. The rest of our microbes we collect from pets, food, water, where we live, our accommodation, whether we are outdoors or indoors, from grooming and food sharing. It’s interesting to note that mice born in a germ free environment have defective guts and poor immune systems with little or no protection.
Your DNA is about 99% the same as the person standing next to you.

However our human microbes are a different story whereby you might only share 10% similarity. There are an astonishing 4lbs of microbes that totally outnumber us: 10 trillion human cells verses 100 trillion microbial cells and our 20,000 human genes are outnumbered again by 2-20 million microbial genes. This is all going on in your nine metres of digestive tubing. Your gut, essentially acting like a bioreactor takes in food that is broken down in the small intestine, where the small simple sugars are absorbed and larger more complex plant material passes through into the colon. Here it’s fermented by bacteria and ends up as short chain fatty acids. It’s a very fine tuned piece of equipment.

Microbes disease and behaviour

The research around microbes and disease states is vast. We can now tell within 90% accuracy if you are lean or obese (obviously you can see that by looking at someone) just by looking at your microbes. If you put the gut flora of an obese mouse into a lean mouse – guess what.. yep the mouse get’s fat. Hormones in our guts can regulate appetite, particularly leptin, grhelin and PYY which are produced in the gut. Gut bacteria can raise tryptophan generating production of these hormones so our microbes can be impacting on how hungry we are and potentially what foods we choose.

Probiotic food can help produce GABA (gamma amino butyric acid) which dampens down excitable neurones and relaxes you – similar to alcohol and valium. Stress and surgery can also have a negative impact on our microbes. The gut contains a lot of neural circuitry that is present in the brain which is why the gut is often called the second brain. The gut and brain work closely together and the gut itself produces lots of neurotransmitters. If you take morphine (which effects brain function) it shuts down motility in the gut. If you feel nervous you can get butterflies in the stomach. The nervous system in the gut is called the enteric nervous system. The gut is fed into the brain by the vagus nerve. If this nerve is blocked or damaged through injury it has a profound effect on appetite which can cause drastic weight loss. Vagus nerve stimulation on the other hand can drive excessive eating behaviour.

Our gut microbes regulate how many neurotransmitters are made in the gut. They can produce substances that block and influence signals that are delivered to the brain – mainly dopamine and serotonin. Dopamine is associated with reward and pleasure and serotonin associated with mood, memory, sleep and cognition. Half of our dopamine is produced in the gut and as L Dopamine is used to treat Parkinsons, you can start to see how influential our gut microbes are.

Nearly all our serotonin is made in the gut and microbes produce factors that can action this. Low Serotonin is linked to depression so again you can start to see the overlapping disease states that are impacted in your gut. Gut microbes do their own thing in terms of inflammation which is key to many disease states eg. skin conditions. Orally consumed probiotics reduce systemic markers of inflammation both of which can be elevated with acne or psoriasis. Oral probiotics can also regulate the release of pro-inflammatory cytokines within the skin.

Stool testing

Stool testing is a great way of knowing exactly what is going on with your gut and there are a few stool tests around at the moment. Analysing what you have and what you don’t gives you a targeted idea of what you need to be eating more of or less of and no it’s not always fibre – its far more complex than that. Map My Gut is the latest gene sequencing stool test developed by Professor Tim Spector at Kings College which provides a personal comprehensive analysis of your gut microbiome.

Through determining the variety and number of microbes living within your gut, we can form links between your nutritional status, immune system function and some disease states. From only a small sample of a bowel movement, they use the latest state of the art DNA sequencing technology to discover your individual microbiome that is unique to you. From your results Map My Gut scientists at the forefront of microbiome research will deliver a comprehensive constructive report on improving your personal gut microbe diversity for better health and longevity.

Stool testing starts at about £170 which can measure your good and bad bacterias and goes up to £300 – fairly pricey yes but for those who have spent hundreds on weight loss programmes it’s possibly a drop in the ocean depending on where your priorities are. Just taking probiotics and a healthy diet does not necessarily ensure all is well as your ecosystem may need extra help. What we are aiming for is as many different good bacteria as you can, microbial diversity is key for your overall health and longevity. The Map My Gut test measures Bacteroidetes, Firmicutes and, Proteobatceria. You want more Akkermansia which will prevent obesity and give you better insulin sensitivity. It is also an anti inflammatory bacteria which increases with fasting. You want good levels of Bifidobacterium and good levels of Christensenella. which is the “skinny” bacteria. Low levels of F. prausnitzii give you a higher risk of autoimmune and allergic reactions.

Your microbiome acts like an organ performing vital functions; breaking down food, protecting from infection, training the immune system, manufacturing Vitamin B12 and Vitamin K, regulating blood sugar and metabolism and sending signals to the brain that can effect mood anxiety and appetite. Additionally they reduce allergic reactions and even alter whether you have a sweet or savoury tooth. We now know that those who are obese or have diabetes have altered gut microbes. As our bacteria are a whopping 30% lower than they were 50 years ago, we have a way to go to get them up to optimal levels. For anyone who has bowel issues, IBS and IBD, diabetes, any autoimmune disease, allergies, skin conditions, depression, anxiety or obesity or inability to lose weight it is worth looking at stool testing as a way forward to targeted personalised results that can really work long term.

If you would like further information about stool testing, or the Map My Gut test please call Kate on 01323 737814. For more information on Map My Gut go to www.mapmygut.com

About the AuthorKate Arnold

Kate Arnold BA (Hons) Dip ION, PGCert, MBANT
Kate is a Nutrition Consultant, health writer, and motivational speaker. With over seventeen years experience Kate has worked with a wide range of clients including corporates, charities such as Rethink, The Princes Trust, schools, colleges and local government as well as media and music personalities. Kate has seen thousands of clients over the years with ranging health problems, but specialises in gastrointestinal health and fatigue disorders and has a special interest in the microbiome. Kate is presently finalising her MSc research at Middlesex University. She is the nutrition consultant for Dulcolax and also the resident nutrition consultant for Wellbeing Magazine.